Archives ofDisease in Childhood 1993; 68: 507 507 Dizygotic twins discordant for HIV and hepatitis C

virus Arch Dis Child: first published as 10.1136/adc.68.4.507 on 1 April 1993. Downloaded from

Karen M Barlow, Jacqueline Y Q Mok

Abstract Discussion Twin girls were born at 37 weeks' gestation to a Factors that enhance the risk of mother to child mother infected by HIV and hepatitis C virus. transmission of HIV include advanced maternal Twin 1 had symptomatic HIV infection by 9 disease, preterm delivery, and breast feeding.' months but was negative for hepatitis C virus Although not as well documented, evidence is antibody and RNA. Twin 2 became HIV anti- emerging that hepatitis C virus may also be body negative by 15 months but was positive vertically transmitted from infected mothers to for antihepatitis C virus and RNA. their offspring.2" Epidemiological factors that (Arch Dis Child 1993; 68: 507) predispose to the acquisition of HIV and hepa- titis C virus infections often coincide, especially in areas where injecting drug use is prominent. The vertical transmission of HIV is now well Viral coinfections may exert synergistic effects, established. Recent work has also documented and it has been postulated that where HIV and the transmission ofhepatitis C virus from mother hepatitis C virus coinfections occur, immune to . We report a set of dizygotic twins who suppression secondary to maternal HIV infec- were discordant for vertically acquired HIV and tion may result in increased hepatitis C virus hepatitis C virus infection. replication and lead to more efficient transmis- sion to the infant.6 We have shown, in this pair of non-identical Case reports twins, that HIV and hepatitis C virus are trans- Non-identical female twins were born at 37 mitted independently, as suggested by Thaler weeks' gestation by spontaneous vaginal and coworkers.3 It is unlikely that false negative delivery. The mother was an intravenous drug results were obtained for hepatitis C virus testing user infected with HIV and hepatitis C virus. in twin 1, as seroconversion was detected by two Both had neonatal requiring photo- second generation antihepatitis C virus enzyme therapy. Neither were breast fed nor received linked immunosorbent assays that used different blood transfusions. hepatitis C virus polypeptides as antigens. The possibility of 'seronegative' hepatitis C virus http://adc.bmj.com/ infection has been ruled out by the repeated use TWIN 1 ofthe PCR that failed to detect plasma viraemia. Twin 1 ( 2180 g) developed sympto- Coinfection with HIV might be expected to matic HIV infection at 9 months of age with cause immune dysfunction, leading to enhanced persistent generalised , hepatitis C virus replication. In contrast, twin 2, chronic parotitis, intermittent splenomegaly, who was not infected with HIV, was persistently

and thrombocytopenia. Laboratory evidence seropositive and viraemic for hepatitis C virus. on September 29, 2021 by guest. Protected copyright. included results positive for HIV p24 antigen Discordance in HIV infection has been noted and culture. Her CD4 counts were stable around even in monozygotic twins. Insufficient informa- 430 cellsx 106/1 (26% T cells). Serum IgG con- tion exists on the mechanism of HIV infection, centration was raised at 19-6 gA/ (reference range with little agreement on the exact time when 5-0-13-0 g/l). She was negative for hepatitis C vertical transmission occurs. Less is known virus antibody and RNA by polymerase chain about mother to child transmission ofhepatitis C reaction (PCR) at 36 and 54 months. She is virus. The observation of discordance for currently 6 years old and attends normal vertical transmission of HIV and hepatitis C school. virus infection in dizygotic twins suggests that other factors have not been accounted for - such as the role ofthe , viral tropism, and host TWIN 2 or genetic factors that might contribute to the Twin 2 (birth weight 2160 g) became HIV infant's susceptibility to infection. antibody negative by 15 months of age, and she 1 European Collaborative Study. Risk factors for mother-to-child has remained negative for HIV p24 antigen and transmission of HIV-1. European collaborative study. Lancet Regional Infectious culture, with normal immune function. She has 1992; 339: 1007-112. Diseases Unit, City 2 Wejstal R, Hermodsson S, Iwarson S, Norkrans G. Mother to Hospital, Greenbank been positive for antihepatitis C virus antibody infant transmission of hepatitis C virus infection. J Med Virol Drive, Edinburgh and RNA-PCR positive at regular intervals: at 1990; 30: 178-80. EH10 5SB 30, and 70 months. 3 Thaler MM, Park C-K, Vanders DV, et al. Vertical transmis- Karen M Barlow birth, 18, 42, 49, 54, 62, sion ofhepatitis C virus. Lancet 1991; 338: 17-8. Y Mok Clinically she is well with normal growth and 4 Weintrub PS, Veereman-Wauters G, Cowan MJ, Thaler MM. Jacqueline Q Hepatitis C virus infection in whose mothers took Correspondence to: development without any signs of disease. street drugs intravenously. J Pediatr 1991; 119: 869-74. Dr Mok. Recent , however, have shown 5 Nagata I, Shiraki K, Tanimoto K, et al. Mother-to-infant Accepted 31 December 1992 raised alanine aminotransferase values of transmission of hepatitis C virus. J Pediarr 1992; 120: 432-4. mildly 6 Lam JPH, McOmish F, Burns SM, et al. Infrequent vertical 46 IU/l (reference range 10-40 IU/1). transmission of hepatitis C virus. J Infect Dis 1993 (in press).